public int compareVersion(String version1, String version2) {
        String[] arr1 = version1.split("\\.");
        String[] arr2 = version2.split("\\.");
        int i = 0;
        //version1 > version2 return 1, if version1 < version2 return -1
        while (i < arr1.length || i < arr2.length) {
             if (i < arr1.length && i < arr2.length) {
                if (Integer.parseInt(arr1[i]) < Integer.parseInt(arr2[i])) {
                    return -1;
                } else if (Integer.parseInt(arr1[i]) > Integer.parseInt(arr2[i])) {
                    return 1;
                }
             } else if (i < arr1.length) {
                if (Integer.parseInt(arr1[i]) != 0)
                return 1;
             } else if (i < arr2.length) {
                if (Integer.parseInt(arr2[i]) != 0)
                return -1;
            }
            i++;
        }
       return 0;
    }